Chapter 4: Carbohydrate Flashcards
What is Carbohydrate?
Contains carbons, hydrogens, and oxygen in the proportion of 1:2:1.
What are the two types of carbohydrates?
Simple and Complex.
All Carbohydrates are made up of sugars called: (list three examples).
Monosaccharides. 1. Glucose2. Fructose3. Galactose
What is maltose comprised of?
Two glucose.
What is lactose comprised of?
One glucose and one galactose.
What is sucrose comprised of?
One glucose and one fructose.
True or False: Hydrolysis adds water to make a disaccharide into two monosaccharides.
True. This happens in the gut.
What are simple sugars?
Monosaccharides (glucose, galactose, fructose) and dissaccharides (lactose, maltose, sucrose).
What are oligosaccharides?
3 - 12 sugar units, majority of breakdown occurs in the large intestine (bacteria breaks them down and produce gas). Also known as prebiotics.
What are polysaccharides?
100s or 1000s of sugar units.Dextins, glycogens, sugar alcohols (maltitol, sorbital).
What are complex carbohydrates?
Starch, a giant polysaccharide consisting of only glucose.
True or False: Starch is the problem, not what else is in the food.
False. Starch is not the problem, it is what it is paired with that can make it unhealthy. Products with starch and fibre can be quite healthy.
What is glycogen?
Similar structure to starch. Found in animals, starch is found in plants. A place to store energy (mostly in liver).
What is cellulose?
Fibre, a bunch of glucose units. Humans do not have enzymes to break the bonds in fibre apart.
DRI values of Carbohydrates?
45-65% of total kcal.
What is the fibre recommendation?
14g/1000 kcal.
What vegetables are high in carbohydrates? (Starch)
Potatoes, peas, corn, carrots.
What fruits are high in carbohydrates? (Mostly simple sugars)
Bananas (very filling, starchy).
What carbohydrate is found in grain products?
Starch.
What carbohydrate is found in milk?
Lactose.
What carbohydrates are found in milk alternatives?
Simple sugars, starch, oligosaccharides.
Pattern of carbohydrate intake in North America?
Since 1900s, N. A. CHO intake has decreased 25-30%, while fat and protein intake has increased. Refined carbohydrate intake has also increase.
What does the mouth do with carbohydrate digestion?
Some starch is broken down into maltose units by salivary amylase. This is more effective is people eat slowly.
What is in the stomach that helps with carbohydrate digestion and absorption?
The hydrochloric acid in the stomach denatures/inactivates the salivary amylase. No actual carbohydrate digestion takes place here.
Where does most of the digestion and absorption for carbohydrate take place?
The small intestine.
What does pancreatic amylase do?
Digests starch in the small intestine, creates maltose.
What does maltase do?
Breaks down maltose into two glucose units.
Where does glucose, fructose, and galactose get absorbed after the small intestine?
Absorbed through the intestinal wall and into the portal vein (vascular system) to the liver.
What is monosaccharide metabolism in the liver?
First, the fructose and galactose is converted into glucose. Glucose then is used for five main purposes:1. Energy needs of the liver2. (Excess glucose) Stored as liver glycogen 3. Made into nonessential amino acids4. (All previous steps have happened, still have excess) Converted into fat, transported by VLDL to adipose tissue5. Set out into bloodstream to fuel body cells.
What happens when glucose is released into the bloodstream?
Provide energy for most body cells. Goes to the muscles to be used as muscle glycogen.
True or False: brain, CNS, red blood cell only use glucose for energy
True.
True or False: muscle glycogen only fuels muscle cells.
True.
What are three basic facts about glucose?
- Found in small amounts in only plant foods.2. It is an essential nutrient. 3. Main energy source for brain, CNS, and RBC.
What happens to glucose when it is released from the liver?
Arise in the the glucose level in blood. Insulin allows glucose to be used as glycogen in muscles, used by cells for energy, and stored as fat.